1. Field of the Invention
The disclosure relates to an electrical apparatus and a method for verifying a battery module thereof.
2. Description of Related Art
FIG. 1 is a diagram of a conventional electrical apparatus 100. Referring to FIG. 1, conventionally, a pull-down resistor RPL is disposed in the battery 110 that is connected to the electrical apparatus 100 for supplying power. The pull-down resistor RPL is serially connected between the terminal CN1 of the battery 110 and a ground voltage GND. A battery verification module 120 for perform battery verification in the electrical apparatus 100 includes a pull-up resistor RPU, a transistor M1, a resistor RSD1, and processors 121 and 122. The pull-up resistor RPU is connected to a voltage V1 and the gate of the transistor M1, the drain of the transistor M1 is coupled to a voltage V2 and the processor 121, and the source of the transistor M1 is coupled to the ground voltage GND. The resistor RSD1 is serially connected between the terminal DT and the processor 122. In addition, the battery verification module 120 is further connected to the terminal CN2.
When the battery 110 is connected to the terminal CN2 to which the battery verification module 120 is connected through the terminal CN1, the voltage on the terminal DT is equal to the voltage obtained by dividing the voltage V1 according to the resistances of the pull-up resistor RPU and the pull-down resistor RPL. Then, the processor 122 reads the voltage on the terminal DT to distinguish the label of the battery 110. In addition, when the battery 110 is effectively connected to the battery verification module 120, the voltage on the terminal DT drops and accordingly the transistor M1 is disabled. Thus, the processor 121 receives a voltage equal to the voltage V2 and accordingly determines that the battery 110 is already connected to the electrical apparatus 100.
In the conventional battery verification method described above, if a resistor having the same resistance as that of the pull-down resistor RPL in an original battery is disposed into a non-original battery, the battery verification module 120 will not be able to distinguish the non-original battery from an original battery. Accordingly, when the electrical apparatus 100 charges such a non-original battery, safety hazards may be produced due to overcharge.